1. Field of the Invention
The invention relates to audio signal processing, and more particularly to automatic volume adjustment for audio signals.
2. Description of the Related Art
A computer is capable of playing movies or music files such as MP3 and MP4 for entertainment. However, the noise level of a surrounding environment of the computer, may change with changes in the surrounding environment. For example, a surrounding environment of the computer may be noisy during the daytime due to increased activity, but quiet during the early morning or late evening. Thus, users must manually adjust speaker volume of the computer when playing a movie or listening to music, to suit the noise level of the surrounding environment. For example, a louder volume is required when the surrounding environment of the computer is noisy.
In addition to a computer, portable devices, such as notebooks, MP3 players, cell phones, or personal digital assistants (PDAs), may also play music. As such, the noise level of a surrounding environment of the portable devices, is even more likely to change due to the portability of the devices. Accordingly, if the portable device is in a noisy surrounding environment, a louder volume is required and a user must manually increase the volume for playing the music. However, frequent manual volume adjustments, are inconvenient for users. Thus, a method for automatic volume adjustment is required.